Fiber optic gyroscopes (FOGs) are well known in the art. The output of the gyroscope are optical pulses which occur at a rate dependent upon the rate of rotation of the gyroscope. The optical pulses are converted to an analog electric signal by well known photo diode arrays. The FOG instrumentation and display units typically require the gyro signals to be in a digital format; therefore, it is necessary to convert the analog signal to a corresponding digital signal.
One problem with the digital conversion of the analog signal is that random noise in the signal can cause conversion errors. Typically, the older gyro designs produced lower optical power and, accordingly, lower analog signals. Therefore, the signal could be amplified substantially before entering the analog to digital converter. The combination of the photo diode conversion and amplification of the signal typically produced enough RMS noise so that the combination of the random noise and RMS noise could be averaged, offsetting any errors caused by the random noise. However, the development of higher optical power in the FOGs has meant that the front end gain had to be reduced sufficiently to prevent artifacts or "glitches" from saturating the photo detector and gain stages. With the reduction of the front end gain, not enough EMS noise is available to provide adequate noise averaging of the signal, thus, the random noise glitches are still present. Because the A/D converters typically have limited number of bits (typically 8 or 12), even small random noise glitches will cause quantization errors in the A/D conversion.